Yeah. the O ring was over stretched and it had a wavey kind of look, so it was not sealing everything properly. The small leak wouldn't really cause a racing idle, it was just something that CAN cause it, but in my case it was the air leak. If you still couldn't pin point your racing idle, and you already checked the carb slide was seating properly, then make sure there is no air leak between the carb and the reed block, and the reed block and the engine. Make sure all your clamps are on tight, everything is all nice and sealed and not sucking air. If all this checks out, then worse case check your crank seal on the stator side. If that seal is worn or slipped out, then that could also race the idle.